Magnetic separator



March 11, 1958 R. N. PALMER MAGNETIC SEPARATOR 2 Shets-Sheet 1 mud Aui.

' March 11 1958 R. N. PALMER MAGNETIC SEPARATOR 2 Sheets-Sheet 2 Filed Aug. 9, 1952 7 5 9 5 a aw kw a W a m flw Mm T. m w WT M um. m 0 w w W6 6 MUM/W Mm W k? PM m n M w n M a 6 w m fl0 .1 6 6 n u w l A /H A WW 3 z Q y wwm L5 hymw fizzfzzs f7. FZZzzzer 9mm M 9 located against the faces of the bar 44, and are retained in position with respect to the bars by retainer bars 48 secured to the upper and lower edges of the bars 44 by screws 52. The retainer bars 48 are notched at 50 to locate the magnets 54 in properly spaced relation along the bars 44. The magnets are stippled in both elevation and cross section throughout the drawings to distinguish them from other parts of the separator.

The entire assembly of the lower two pole pieces 40, the bars 44, and the magnets 54 is retained in the assembled position by means of tie rods 56 extending through the pole pieces and the bars 44 and provided with nuts 58 for adjustment purposes. The outer nuts are tightened for bringing all parts into snug engagement and then the inner nuts are tightened to serve as lock nuts and retain the parts assembled without relative movement.

Magnetic extension bars 68 are mounted on a pair of extension mounting bars 62 of magnetic material shown in Figure 2 by means of screws 64, and the lower bar 62 is secured to the middle pole piece 48 by means of the upper nuts 58 on the tie rods 56 as illustrated. The upper extension mounting bar 62 is secured to the upper pole piece 48 by bolts 66.

The arrangement just disclosed provides a lower air gap A in Figure 6 between the lower rotor 34 and the lower pole piece 48 of maximum magnetic strength and an upper air gap B between the middle pole piece 48 and the middle rotor 34 of somewhat less strength because part of the magnetism is carried off through the magnetic extension bars 68 to provide a similar magnetic air gap (the uppermost of the three in Figure 1) between the upper pole piece and the upper rotor 34 which is even weaker than the gap B. Thus there is a progressively stronger magnetic field acting on the mineral or other material being magnetically separated as the material passes through the machine.

The magnetic eflect of the magnets 54 may be reduced by means of magnetic shunts 68 in the form of plates of magnetic material which short circuit part of the magnetism from the lower and middle pole pieces 40. The plates 68 are each mounted by one upper set screw 70 and two lower set screws 72 which provide a three-point support. As shown in Figure 4, this provides an air gap C between 68 and the retainer bars 48 and the gap may be adjusted by rotation of the set screws 70 and 72. The set screws are threaded in the magnetic shunts 68 and due to the magnetic attraction of the pole pieces 40 with respect to the shunts 68, the pole pieces being energized of course by the magnets 54, the magnetic shunts remain in the position illustrated by merely providing reduced ends 74 on the set screws 70 and 72 to enter sockets 76 of the pole pieces 40.

Above each rotor 34 I provide a chute assembly 78. The chute assembly comprises a primary chute 80, a secondary chute 82, a divider or knife edge 84 on the primary chute, and a bafile 86. A slot 88 is provided in the primary chute 80 adjacent the baffle and a chute cover 90 is provided for the chute 78 as best shown in Figure 6.

The chute assembly 78 is mounted on a pair of mounting tracks 92 pivoted at 94 to the bearing housings 31.

Each mounting track 92 is provided with an adjusting rod 96 pivoted thereto, which extends through the supporting plate 28 and the supporting bar 26 as shown in Figure 8. The bar is provided with a set screw 98 for the purpose of retaining the adjusting rod in a desired adjusted position.

A tailings chute 100 is provided as shown in Figure 6 below each of the rotors 34, and it will be noted by reference to Figure 1 that one of the chute assemblies 78 is also provided below the lower rotor 34.

The mounting track 92, as shown in Figure 8, is grooved as at 102 to receive a slide 106. The chute assembly 78 is supported on supporting bars 104 and is connected by clamp screws 108 to the slides 106 so that the primary chute 80 and its divider 84 can be adjusted upwardly along the mounting tracks 92 as shown by dotted lines in Figure 6, and its angle may also be adjusted as likewise shown by the dotted line position of the mounting tracks 92.

In Figure 6 I have indicated in circles the north and south poles of the magnets 54 by the characters N and S encircled. The resultant north and south poles for the pole pieces 40 and the rotors 34 are similarly indicated.

Practical operation in the operation of my magnetic separator, reference is made particularly to Figures 1 and 6. The mineral from which magnetic particles are to be separated is deposited in the hopper 22 and flows into the vibratory chute 2 4. From there it flows over the top edge of the divider 84 shown in section in Figure l and into the uppermost primary trough 86 down which it slides in the manner illustrated in Figure 6. It attains a certain speed of fiow and the angle of the chute assembly '78 is adjusted so that the flow is entirely free. However, free flow is too fast for proper magnetic separation in the air gap between the upper rotor 34 and the upper pole piece 40. I, therefore, provide the ballie 86 just below the slot 88, and the material strikes the baflle thus arresting its flow and it thereupon flows through the slot and into the secondary chute 82 where the flow is short so that the material does not have a chance to attain too much momentum. Just the right momentum can be regulated by changing the angle of the chute assembly 78 at the set screws 98.

The material to be separated flows over the first or upper rotor 34 and part of the magnetic material is separated out; whereas the rest of the material flows on to the middle rotor 34 and more of the magnetic material is removed from the flowing material as will now be described in connection with Figure 6. After this description of Figure 6, it will be obvious how separation takes place at the upper rotor 34 in Figure 1 in a manner similar to the middle rotor 34 (which is the upper one shown in Figure 6).

The non-magnetic material and some slight portion of the magnetic material will fall in a trajectory indicated at 110. The curvature of the trajectory depends on the speed of the material as it comes olf the rotor. Assuming a trajectory 110 as illustrated in Figure 6, the material referred to goes to the right of the divider 84 as illustrated so as to fall into the primary chute 80.

A trajectory 112 is shown for the magnetic particles which tend to follow the surface of the rotor 34 and the trajectory 112 is therefore separated from the trajectory 110 and falls to the left of the divider 84. This magnetic material falling along the trajectory 112 lands in the tailings chute and flows out as illustrated.

If it is desirable to increase the angle of the chute assembly 78 to speed up the flow of the material yet retain the same speed of rotation of the rotors 34, the mounting tracks 92 may be adjusted to the dash line position shown in Figure 6 and the primary chute assembly adjusted upwardly along these tracks so that the divider 84 is at a position such as 84a and still substantially halt-way between the trajectories and 112. Likewise the angle of the chute assembly and the position of the divider may be adjusted for a faster or slower rotating rotor and for the character of the material being passed through the magnetic separator.

A small percentage of the magnetic material is separated in a trajectory similar to 112 just described from the upper rotor 34, additional material is separated as just described in connection with Figure 6 and further magnetic material is separated as at 112a from the material in the trajectory 110a at the lower rotor 34 in Figures 1 and 6. Finally the material issues as at 1101: in Figure 1 and contains very little or no magnetic material. By having the maximum magnetic field at A in Figure 6, less magnetic field at B, and still less between sive and is accomplished with the, greatest efficiency,

When operating on material of with character that greater. magnetic infliienee is desirable from the magnets V 54, the shunts 68 can be removed. on the other hand,

when it is desirable to reduce the magnetism, this may be accomplished by short-circuiting some of it by adjusting the shunts 6s closer to theretainer' bars 48 for reducing the effect of the magnets 54 on the pole pieces 40. Also the magnetic gap shown at B for instance in Figure 3, can be increased in diiifiension by roper ad justinent of the screws tz and 43 (see Figure 3a) be tween the pole piece 40 and-the hearing housings 31. This would increase the spacing as" to the dimension B in Figure 3, a I h Asalready descrihed, the angle of the chute assembly and the position of the divider 84ihay be readily adjusted to take care of diiie'reiit speeds of operation and different materials being worked upon. It has been found that arotor surface, which is not continuous but interrupted with non-metallic portions is superior to one that is formed entirely of magnetic material and I provide a relatively economical arrangement for manufacturing such rotors as described above in cor'inection With Figme 5'. By having the rotor surface interrupted hy grooves filled with non-magnetic material such as ah'a'rdened plastic, I provide a converging magnet c field befsystems tween the ungroov ed portions of the rotor and the edjaeent pole piece. p

While in the foregoingdescription I have made reference to three raters 34, the number may be infeiease'd or decreased depending on the re uirements, My ma-gneti'zing arrangement for the pole piece 40 as well as t.

.the shunt 68 used in connection therewith and the chute assembly disclosed may in fact he used in connection with a single rotor where only one is sufficient for the magnetie separation needed.

From the foregoing specification it will be obvious that I have provided a magnetic separator which will accomplish the objects set forth in my specification and yet is economical to produce since it uses permanent magnets, thus eliminating the necessity of providing eleet'ric current for electromagnets and the necessar equipment for ehanging' alternating current to direct current where required. 7

Some changes may be made in the construction and arrangement of the parts of my magnetic separator without departingfrom the real spirit and purpose of myi-nvention,-*and;it is my intention to cover by my claims any modified forms ofstructure or use of mechanical equivalents which may be reasonably included within their scope. e i

I claim as my invention: I I

l. A magnetic separator of the character disclosed comprising, a frame structure, a base plate supported thereby, a plurality of spaced rotors rotatably mounted thereon and having their axes in a plane substantially inclined them the vertical, means for magnetizing said rotors comprising permanent magnets extending substantially parallel to said planefrom rotor to rotor, polepieces at the ends of said magnets to be magnetized there- By, said pole pieces being spaced from said rotorsto providemagnet'ie airgaps through which material to'he' separated may flow; chute means also substantially parallel to said plane for feeding material to be separated through said magnetic air gaps, dividing means at the discharge of each rotor for dividing the magnetic particles separated from said material, said chute means being adjustable as Y to inclination and said dividing means being adjustable relative to said chute means.

2. In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors rotatably mounted thereon, means for magnetizing said rotors comprising permanent magnets extending item rotor to ate pets pistes at the. ends or said ma nets to i iiiagiietized; threhfi niagrietic' eXterisions from one of said pale pie s to adjacent another of said rat rs, a pole sites at the on e'i endsofsaid magnetic extensions; to be magnetized thereby, said pore pieces terminating adjaeent hut spaced from said rater to, provide magnetic air gaps th'r ugh wijieii material to be separated my new, a same assemiity for delivering r'r'i aterial tohe' separated to each said raters, said eiiujte assembl being 'pivotallv r'iioiiiited ad acent the rotor and adjustable about the pivotal ,c'ennecti '11, a divider carried by each chute assemhl y afrd adjstahle; along the chute assembly, said eliiite assehihl'j" irieliiding a primary chute leading from said divider, a secondary chute below said primary chute arid a battle adjaeefit' the discharge end of said primary secondar etiute be ngeomparatively short to minimize the attainment streiecity or the material as it flaws therealo'fig';

a ma netic separator, ai frame structure, a base piste siippetted iieiety, a plurality of space rotors retata y mounted thereon, means for magnetizing said roo'le' pieces spaced from said rotors to prev'ide magn" 1c gaps through which material to he separate'drn fl w; a chute assembly for deliveringIma- *1 to" be separated to each or said raters in tandem, eac of said chute assemblies being pivotally mounted adjacent therefor '26 which it delivers material and ad'- justable about, the pivotal connection, and a divider car'- ried hy "eat .chute assembly sea adjustable along the assernhli reward therotor from whieh it receives 'etie" separates; a frame structure, a Base edftl! sy' a plurality of spaced rotors re ta'taliiy mounted thereon, means for magnetizing said rotars iricl 'udirig pale pie'ees spaced formsaid' rotors to air' gaps through which material to" be separa 1 flow, a ehute assembly for delivering material to be separated to each of said rotors in tandem, each (if said c" assemblies being pivotally mounted adjacent the re 1' ts it delivers material and adjustable ahout the pivotal connection, a divider carried s9 ea c'h chute assembly and adjustable along the chute assembly tower the rotor from which it receives material, said chut assembly including a primary chute leading from said divider; asecondary chute below said priiiiary' chute and abarns beyond the discharge end of the pr ry chute to slow down the flow" of the material arid change the direction of its course into the second chute, said haffije being close to the discharge end of said seeondary chute. p

5 In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors therean; means for magnetizing said rotors comprising permanent magnets, pole pieces spaced from said rotors arid magnetized by said magnets to provide magnetic air gaps through which the material to be separated flows, a chute assembly for delivering material to each of said rotors, said chute assembly being pivotally mounted adjacent the rotor to" Whichit delivers material and adjustable about its pivotal mounting a divider carried by each chute assembly and adjustable along the chute assembly toward the rotor from which it receivcs'material, said chiite' assenibly including a primary chute leading frem said divider, a secondary chute below said primary chute and a hafiie adjacent the discharge end of the primary chute to slow down the flow of the material and change its direction as it flow's into the secondary chute, said secondary chute being relatively steep to insure free flow of the material and being compartively short to minimize V the attainment of velocity by the material as it flows therealong} as'hu'nt for said magnets and means for adjusting in said magnetic air gaps.

6. In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors rotatably mounted thereon, means for magnetizing said rotors comprising permanent magnets, pole pieces extending from the poles thereof to positions adjacent said rotors to provide magnetic air gaps through which the material to be separated flows, a chute assembly for delivering material to each of said rotors, said chute assembly being pivotally mounted adjacent the rotor and adjustable about its pivotal connection, a divider carried by each chute assembly and adjustable along the chute assembly, a shunt for said magnets, and means for adjusting said shunt toward said magnets to reduce the magnetism in said magnetic air gaps.

7. In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors thereon, means for magnetizing said rotors comprising permanet magnets and pole pieces spaced from said rotors to provide magnetic air gaps through which the material to be separated flows, chute means for feeding material to be separated through said magnetic air gaps, dividing means at the discharge of each rotor for dividing the magnetic particles separated from said material, a shunt for said magnets, means for adjusting said shunt toward said magnets to reduce the magnetism, means for mounting said magnets on said pole pieces comprising tie rods connecting said pole pieces together and clamping said magnets between them, and retainer bars along opposite edges of the pole pieces to retain said magnets located in relation thereto.

8. In a magnetic separator, a frame, a base plate supported thereby, a plurality of spaced rotors mounted thereon, means for magnetizing said rotors comprising permanent magnets and pole pieces spaced from said rotors to provide magnetic air gaps, chute means for feedmg material to be separated through said magnetic air gaps, means for mounting said magnets on said pole pieces comprising tie rods extending substantially parallel to said magnets, connecting said pole pieces together and clamping said magnets between them, and retainer bars along opposite edges of the pole pieces to retain said magnets located relative to said pole pieces.

9. In a magnetic separator, a frame, a base plate supported thereby, a plurality of spaced rotors thereon, means for magnetizing said rotors comprising permanent vmagnets, pole pieces spaced from said rotors to provide magnetic air gaps through which the material to be separated fiows, said pole pieces being magnetized by said magnets, a shunt for said magnets, means for adjusting said shunt toward said magnets, and means for mounting said magnets on said pole pieces comprising tie rods extending substantially parallel to said magnets, connecting said pole pieces together and clamping the ends of said magnets against said pole pieces.

10. In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors mounted for rotation thereon, means for magnetizing said rotors comprising permanent magnets and pole pieces spaced from said rotors to provide magnetic air gaps through which the material to be separated flows, a chute assembly for delivering material to each of said rotors, said chute assembly being pivotally mounted adjacent the rotor and adjustable about its-pivotal mounting, a divider carried by each chute assembly and adjustable therealong, said chute assembly including a primary chute leading from said divider, a secondary chute below .said primary chute and a bafile adjacent the discharge end ofthe primary chute to slow down the flow of the material and change its direction as it flows into the secondary chute, a shunt for said magnets, means for ad justing said shunt toward said magnets to reduce the magnetism in said magnetic air gaps, and means for mounting said magnets on said pole pieces comprising tie rods connecting said pole pieces together with said magnets interposed between them.

ll.- In a. magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors rotatably mounted thereon, means for magnetizing said rotors comprising permanent magnets extending from rotor to rotor, pole pieces at the ends of said magnets to be magnetized thereby, magnetic extensions from one of said pole pieces to adjacent another of said rotors, a pole piece at the outer ends of said magnetic extensions to be magnetized thereby, said pole pieces being spaced from said rotors to provide magnetic air gaps through which material to be sepaarted may flow, a chute assembly for delivering material to be separated to each of said rotors, said chute assembly being pivotally mounted adjacent the rotor to which it delivers material and adjustable about the pivotal mounting, a divider carried by each chute assembly and adjustable along the chute assembly toward the rotor from which itreceives material, said chute assembly including a primary chute leading from said divider, a secondary chute below said primary chute, and a baflle beyond the discharge end of the primary chute to slow down the flow of the material and change the direction of its course into the secondary chute, said baffle delivering the material close to the discharge end of said secondary chute.

12. In a magnetic separator, a frame structure, a base plate supported thereby, a plurality of spaced rotors rotatably mounted thereon, means for magnetizing said rotors comprising permanent magnets extending from rotor to rotor, pole pieces at the ends of said magnets to be magnetized thereby, said pole pieces being spaced from said rotors to provide magnetic air gaps through which material to be separated may flow, a chute assembly for delivering material to be separated to each of said rotors, a divider carried by each chute assembly and adjustable along the chute assembly, said chuteassembly including a primary chute leading from said divider, a secondary chute below said primary chute, and a baflle beyond the discharge end of the primary chute to slow down the flow of the material and change the direction of its course into the secondary chute, said secondary chute being comparatively short to minimize the attainment of velocity of the material as it flows therealong.

13. In a magnetic separator, a frame structure, a base plate supported thereby, a rotor journalled thereon, means for magnetizing said rotor comprising permanent magnets and a pole piece at the ends of said magnets to be magnetized thereby, said pole piece being spaced from said rotor to provide a magnetic air gap through which material to be separated may flow, chute means for feeding material to be separated through said magnetic air gap to the intake side of said rotor, dividing means at the discharge side of said rotor for dividing the magnetic thereof by said pole piece, toward said magnets to reduce their magnetic etfect on said pole piece and said rotor.

14. Amagnetic separator of the character disclosed comprising a frame structure, a base plate supported thereby, bearing housings mounted thereon, a rotor rotatably journalled in said bearing housings, means for magnetizing said rotor comprising permanent magnets and a pole piece at the ends of said magnets to be magnetized thereby, said pole piece being spaced from said rotor to provide a magnetic air gap through which material to be separated may flow, chute means for feeding A material to be separated through said magnetic air gap,

said chute means being pivoted adjacent its discharge end to .said beaing housings, and means for adjusting ts inclination, the discharge end of said chute remaining in substantially the same relation to the rotor to which it delivers material in all positions of chute adjustment.

References Cited in the file of this patent UNITED STATES PATENTS Snyder Dec. 28, 1909 10 Ullrich Dec. 13, 1932 Tyden July 3, 1934 Payne June 23, 1936 Stearns Apr. 27, 1937 Ballantine July 4, 1939 Carpenter 1. Oct. 23, 1956 FOREIGN PATENTS Great Britain May 8, 1933 

